Two men were shot and killed early Thursday in a span of four hours in East Oakland, police said.

Shortly before 9:30 a.m., a man was found dead at a home on the 6300 block of MacArthur Boulevard. The cause of his death was not immediately released, but police were investigating it as a homicide.

Earlier, just after 5:30 a.m., 24-year-old Kyal Porter was shot while riding a bicycle on the 9800 block of A Street, witnesses told police. He was pronounced dead at the scene.

The city's gunfire-detection system reported that about 17 rounds were fired, police said.

Porter's father, 52-year-old Wendell Porter, told reporters, "You hear about killings all the time out here in Oakland. You hear a lot about that, and it's around you. You never think it would hit you directly, but it's hit me."

He added, "It needs to stop. What is it going to take to stop? I mean, it goes on and on."